AdvRocketry: 2.0.0.-257 (no unstable builds available)
LibVulpes: 0.4.2.-88
MC: 1.12.2

• This occur without other mods installed

Crash report (debug.log)

Description

ANY recipe of Chemical Reactor that has itemStack in output crashing game.

1. Build Chemical Reactor
2. Put Bone + Nitrogen in input hatches (default recipe)
3. Wait before recipe complete
4. Crash

Can confirm, I'm having the same issue using AdvancedRocketry-1.12.2-2.0.0-13

Can also confirm, AdvancedRocketry-1.12.2-2.0.0-13

Can also confirm, it happens also with other recipes of the Chemical Reactor.
AdvancedRocketry-1.12.2-2.0.0-13
LibVulpes-1.12.2-0.4.2-25-universal